The bot is a Twisted IRC client. Check out the [Twisted documentation](http://twistedmatrix.com/documents/12.2.0/api/twisted.words.protocols.irc.IRCClient.html) and the [ircLogBot example](http://twistedmatrix.com/documents/current/core/howto/clients.html#auto5) for more information.

Oh and of course: [Berend Botje](http://nl.wikipedia.org/wiki/Berend_Botje_ging_uit_varen)